Title
Local earthquakes of the Mexico basin in Mexico city: κ, Q, source spectra, and stress drop
Date Issued
01 August 2016
Access level
metadata only access
Resource Type
journal article
Author(s)
Lermo J.
Santoyo M.A.
Jaimes M.A.
Chavacán M.
Universidad Nacional Autónoma de México
Publisher(s)
Seismological Society of America
Abstract
We analyzed 14 local earthquakes of the Mexico basin (2:3 ≤ Mw ≤3:8), recorded on hill sites at local distances (8:0 ≤ R ≤ 60:5 km), to study the spectral attenuation of seismic waves, spectral decay parameter kappa κ, quality factor Q, source spectra, and Brune stress drop. We found an average κ0-value of 0.0457 s in hill sites, which is similar to values reported in other regions. Assuming a 1=R geometrical spreading, we obtain a quality factor given by Q(f) = 72f0:83. Source spectra of all studied events are in good agreement with the ω2 model. From the synthetic modeling of ground motions at local distances, we explain an anomalous behavior of the corner frequency versus seismic moment and also explain the relatively low values observed for stress drop (5 MPa). The resulting high spectral attenuation values obtained may be responsible for the low acceleration values of ground motions observed for crustal earthquakes occurring inside and near to the Mexico basin.
Start page
1423
End page
1437
Volume
106
Issue
4
Language
English
OCDE Knowledge area
Geoquímica, Geofísica Geología
Scopus EID
2-s2.0-84982306892
Source
Bulletin of the Seismological Society of America
ISSN of the container
00371106
Sources of information: Directorio de Producción Científica Scopus